Nomenclature A.M. Clark (1967) proposed to the ICZN to suppress the older name O. pentaphylla in favour of the more widely applied name...

Nomenclature A.M. Clark (1967) proposed to the ICZN to suppress the older name O. pentaphylla in favour of the more widely applied name fragils. That proposal seems never to have been decided and technically, O. pentaphylla has priority. Since O. fragilis has been in prevailing usage for about a century, changing that would cause instability. However, the article on prevailing usage does not apply because the name pentaphylla has been used after 1899. [details]

Distribution Low intertidal to 150 m depth, under stones on the shore and often in dense aggregations offshore (see Warner, 1971 and...

Distribution Low intertidal to 150 m depth, under stones on the shore and often in dense aggregations offshore (see Warner, 1971 and Broom, 1975 for descriptions of behaviour) on rough and gravelly ground; common all round the British Isles in places with strong currents [details]

Nomenclature A.M. Clark (1967) proposed to the ICZN to suppress the older name O. pentaphylla in favour of the more widely applied name fragils. That proposal seems never to have been decided and technically, O. pentaphylla has priority. Since O. fragilis has been in prevailing usage for about a century, changing that would cause instability. However, the article on prevailing usage does not apply because the name pentaphylla has been used after 1899. [details]

Distribution Low intertidal to 150 m depth, under stones on the shore and often in dense aggregations offshore (see Warner, 1971 and Broom, 1975 for descriptions of behaviour) on rough and gravelly ground; common all round the British Isles in places with strong currents [details]